An important function of the Core staff is to make biostatistical consultation readily available to each of the Center investigators - from the time an idea comes to mind, through the design, execution, analysis and reporting of the results. This consultation is available in one-to- one consultation and consultation with research teams as well as upon attendance at the monthly meetings of the whole group of Center investigators where we comment on each of the ongoing studies, whether or not the investigators have seen the need for private consultation. Other important missions of the Core are to ensure that the data collected ar of high quality, that the statistical methods used by the investigators are state of the art, that statistical methods are modified to fit the special needs of each study and that new methods reported in the literature are adapted and used where appropriate in the studies done by Center investigators. Through the past 5 years - during the existence of the Biostatistical Core Unit - the investigators have participated in all 7 of the projects supported by the Center grants. Biostatisticians have collaborated as joint authors in 16 of the published papers and have been acknowledged explicitly in many others. Simulated by these collaborations and consultations the biostatisticians have published an additional 14 papers reporting on innovations and methodological advances of general interest to statisticians and biomedical investigators. Additionally, the Core investigators are now actively collaborating with more than twenty non- MAMDC funded investigators, both at Stanford University and at other institutions, in arthritis related investigations.